The U.S. Geological Survey, at the request of the rational Park Service, participated in a field symposium May 22-26, 1967, at Mammoth Cave National Park, Kentucky. This symposium, held by the National Park Service, was to determine the applicability of the Wilderness Act of 1964 to underground and surface portions of the Park (W. Drew Chick, Jr., written communication, 1967). Scientific evidence bearing on the relationships between human surface activities and natural underground openings was examined and discussed at the symposium. This report discusses relations between various types of surface activities and physical damage to the cave openings and features. Additional interpretive material is taken from the literature and from limited laboratory information. Possible hydrologic and biologic effects are not considered here, but were investigated by other members of the symposium. Hydrologic effects are discussed in companion report by Robert V. Cushman of the Geological Survey.